Jump to content

Talk:Controlled combustion engine

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Rotational mass problems?

[edit]

The big problem with this technology is probably that the lobes will act as flywheels, so the engine will be slow to change its revolutions because of the huge inertia in the spinning lobes.

the cams are quite small, and probably could be hollowed out to save weight. The weight of the piston rods and the "big-end" and "small-end" are also eliminated. The CCE engine eliminates or simplifies parts and saves weight. Hence, inertia is surely not a problem.
"the cams are quite small" is marginally helpful. The rest is a great example of Ignoratio elenchi. Can you disclose the dimensions and weight of the cams?
Why should the rotating lobes of the cams replacing the crankshaft have any more inertia than a normal crankshaft would? Also, if you do the math you'll realize that the cams only rotate at one third of the RPMs of the equivilant crankshaft. I.E. While a normal crankshaft would rotate 720 degrees per full four-stroke cycle, a CCE lobe-pair would only rotate 240 degrees.
supply the moment of inertia of the cams then I'm sure people would happy to "do the math". It also occurs to me that the flywheels concern is not a concern if this is to be used as an aircraft engine or a pump.
From Revetec, No matter what arguments are put forward, we have made our engines rev freely at the same or faster rate than a conventional engine. Our Trilobes rotate at 1/3 engine speed and do not have as much inertia to rotate as much as a conventional crank. Thank you for your comments though. —Preceding unsigned comment added by Revetec (talkcontribs) 23:36, 22 November 2007 (UTC)[reply]
specious argument as is doen't address the flywheel concern.


Concerning the rotational mass problem. I think it's likey that the previous protypes had some very serious vibration problems. It's also quite clear that Revetec knows that this is the case. I have no doubt that this is what motivated the design of the X4. The X4 is the first engine with active balancing. Why would they do this unless the previous prototypes had this problem? But...that's all water under the bridge. The current X4 looks like it is well balanced. However, the concern over acceleration with the cam/flywheel issue might have some merit.War (talk) 07:34, 7 March 2008 (UTC)[reply]

Proposed design still?

[edit]

If its a shipping product (according to the Revtec website and customer comments) then I'd consider it well beyond the research stage. The category:Proposed engine designs is probably outdated in that regard as well.--Hooperbloob 14:49, 17 October 2005 (UTC)[reply]

The engine design is not currently shipping in any production items. It has been proven to run, and installed into a car and trike, and has had investment made by an automotive company, but can still be considered only proposed as you are unable to, as an individual, go out and buy a vehicle or pump or similair item from a store that has one of these engine components inside of it.
Not to mention the engine itself is impossible to acquire. According to thier site it's not in production. They've made multiple prototypes over the years but that's it so far. Personally, I'm looking forward to the day we can see and test a production engine.War 09:06, 16 October 2007 (UTC)[reply]
[edit]

I'm concerned that the majority of text in this topic is copied from other sources. In fact, much of it comes from the revetec company web site. Has proper permission been given to put this information here? War 09:00, 16 October 2007 (UTC)[reply]

From Revetec, It is either:

1) Have inaccurate information on Wikipedia or,

2) Allow us or others to post more accurate information.

Whatever the users/readers want, it is up to them.

Proposal moving Revetec info to Revetec

[edit]

This page is riddled with information about the Revetec company itself. I think the content would be clearer and sound less bias if much of this information was moved to the Revetec topic and the redirection removed. Thoughts? —Preceding unsigned comment added by War (talkcontribs) 09:22, 16 October 2007 (UTC)[reply]

Neutrality

[edit]

This article reads like an advertisement. I hope that it can be cleaned up so that it contains as much verifiable facts as possible. I added the POV tag to hopefully bring this to peoples attention so that they can help improve this article.War 22:02, 27 October 2007 (UTC)[reply]

I think that you should be qualified in an area that you want to make a contribution, especially to put a POV on the Revetec subject.

I think that if we look at a subject such as Harley Davidson and view the discussion on handling and vibration as well as make performance comparisons to Japanese bikes then the Harley Davidson article also becomes bias.

That's called a red herring. The above has no bearing on this article. Please put comments about Harley Davidson article bias on the Harley Davidson talk page.War (talk) 15:49, 24 November 2007 (UTC)[reply]

I'm still concerned over the neutrality. The article has a long list of "Advantages". Most of the items are cited by a link to the companies website. I don't think this qualifies as a valid citation.War (talk) 00:01, 24 May 2008 (UTC)[reply]

According to Wikipedia:Reliable sources a citation to the company website doesn't cut it. It needs to be third part at the very least. Since these have been around awhile and no citation that stands up the standard has materialized...I will remove the items from the list. —Preceding unsigned comment added by War (talkcontribs) 00:05, 24 May 2008 (UTC)[reply]

Efficiency

[edit]

There seems to be some implication from Revetec that they have proved that it has good fuel consumption. They (Revetec) may well have that information, but the Nov 19 report does not contain that info. It gives a power curve, a fuelling map and the measured air/fuel ratio... but that still leaves one variable out of the equation. Greg Locock (talk) 05:19, 9 January 2008 (UTC)[reply]

In April 2008, Revetec completed their first Independently Certified Test Report carried out by Orbital Australia, achieving a repeatable BSFC figure of 212g/kW-h (38.6% efficiency) with a best tested figure of 207g/kW-h (39.5% efficiency). We are now designing a more efficient top end to increase overall efficiencies in all rev/load ranges. Is that OK for you Greg? —Preceding unsigned comment added by Revetec (talkcontribs) 19:49, 23 May 2008 (UTC)[reply]

Yes I was quite impressed by that report. I'm a little nervous that running lean produces gof economy - not exactly news, and may not be sufficiently durable. Greg Locock (talk) 01:38, 24 May 2008 (UTC)[reply]
The latest report is much better: http://www.revetec.com/pdf/REVETEC%20X4V2%20Engine%20Evaluation%20Report_final.pdf
The reports states the quoted effieciency: 38.6% and 39.5% but to imply that this compares to the BSFC numbers of a typical automative engine is just wrong. To quote the BSFC article, "A typical cycle average value of BSFC for a gasoline engine is 322 g/(kW·h). This means the average efficiency of a gasoline engine is only 25%." Note the reference to the AVERAGE efficiency. The present article presents MAXIMUM values. It's extremely misleading.
I hope someone will beat me to it. If not I will definately either remove the misleading information or extensively modifying it.War (talk) 23:57, 23 May 2008 (UTC)[reply]


I've got a problem with that. The Orbital report IS a third party report by a notable entity. Are you saying we shouldn't quote the Ford website in the Ford article? Absurd. The question is not what the guidelines say, the real question is, does it make for a better Wiki article? The information is objective, relevant and interesting. I vote it stays. Greg Locock (talk) 01:38, 24 May 2008 (UTC)[reply]
I have no problem with the Orbital reference. I agree that information from it should be included. What I have issue with is claims that the company makes that are backed only by a marketing page on thier website.War (talk) 06:02, 24 May 2008 (UTC)[reply]


Claimed advantages

[edit]

I've put most of the claimed advantages back in. They don't need cites as such, there is no doubt that Revetec claim the advantages, what they need is some proof that the claim is reasonable or works for the stated reasons. Another approach would be to start a technical critique section, but that veers very close to OR. It might be worth rewriting the claims into a form that is more easily referneced in this fashion. eg "The Revetec engine has a Blodwyn interchanger. This is claimed to improve the efficiency of the gargle extractor by 7%, and so result in increased puffledom". Sentence 1 is the claim , and does not need a ref beyond the marketing page. The second sentence needs a technical ref affirming that Blodywn interchangers do increase the efficiency of the gargle extractor, and that this does result in increased puffledom. Greg Locock (talk) 01:52, 25 May 2008 (UTC)[reply]

Is the word lean of any significant meaning?

[edit]

Couldn't the sentence in the article "Efficiency - Recent tests gave good results, for a gasoline engine, when running lean." be written as "Lean - Recent tests gave good results, for a gasoline engine, when running efficient.". To me lean is just a more abiguous way of saying efficient. —Preceding unsigned comment added by Duke sandpaper (talkcontribs) 04:23, 16 April 2009 (UTC)[reply]

No, lean has a specific meaning. Greglocock (talk) 04:30, 16 April 2009 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just added archive links to 2 external links on Controlled combustion engine. Please take a moment to review my edit. If necessary, add {{cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—cyberbot IITalk to my owner:Online 21:25, 9 January 2016 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just added archive links to 2 external links on Controlled combustion engine. Please take a moment to review my edit. If necessary, add {{cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true to let others know.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—cyberbot IITalk to my owner:Online 00:35, 12 February 2016 (UTC)[reply]

[edit]

Hello fellow Wikipedians,

I have just modified one external link on Controlled combustion engine. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 17:25, 12 August 2017 (UTC)[reply]